Clearwater Rapid Watershed Assessment
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Clearwater - 17060306 Idaho 8 Digit Hydrologic Unit Profile December 2006 Tensed Farmington Clearwater - 17060306 8-Digit Hydrologic Unit LATAHLATAH Location Map Potlatch Bovill WHITMAN WHITMAN Deary (Washington) (Washington) Elk River Troy Moscow CLEARWATERCLEARWATER Kendrick Juliaetta Genesee Pierce Clearwater Peck Orofino Clarkston 17060306 Lapwai Culdesac Weippe Lewiston Asotin Reubens LEWISLEWIS Kamiah Craigmont Winchester Nezperce Kooskia Ferdinand NEZNEZ Stites PERCEPERCE Cottonwood !COEUR d ALENE MOSCOW! IDAHOIDAHO Grangeville LEWISTON! !REXBURG CALDWELL! !BOISE NAMPA! !IDAHO FALLS : BLACKFOOT ! !POCATELLO 0 5 10 15 20 25 TWIN! FALLS Miles The United States Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, sex, religion, age, disability, political beliefs, sexual orientation, and marital or family status. (Not all prohibited bases apply to all programs.) Persons with disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA’s TARGET Center at 202-720-2600 (voice and TDD). To file a complaint of discrimination, write USDA, Director, Office of Civil Rights, Room 326W, Whitten Building, 14 th and Independence Avenue, SW, Washington DC 20250-9410 or call (202) 720-5964 (voice and TDD). USDA is an equal opportunity provider and employer. 1 Clearwater - 17060306 Idaho 8 Digit Hydrologic Unit Profile December 2006 Introduction The Clearwater 8-Digit Hydrologic Unit Code (HUC) subbasin is 1,503,992 acres. Clearwater and Nez Perce counties each account for approximately 24 percent of the subbasin. Twenty two percent of the subbasin is in Latah County, 18 percent in Lewis County, 13 percent in Idaho County and less than 0.5% in Whitman County, Washington. Seventy seven percent of the basin is privately owned, five percent is Tribal land and 18 percent is public land. Forty percent of the basin is in forest, 34 percent is cropland, and 21 percent is shrubland, rangeland, grass, pasture or hayland. Approximately 3 percent of the watershed is enrolled in the Conservation Reserve Program (CRP). The remaining two percent is water, wetland, developed or barren. Elevations range from 700 feet in the western portion to over 6000 feet in the eastern portion. Conservation assistance is provided by five Soil and Water Conservation Districts, and one Resource Conservation and Development office. Profile Contents Introduction Resource Concerns Physical Description Census and Social Data Landuse Map & Precipitation Map Progress/Status Common Resource Area Descriptions Footnotes/Bibliography Resource Settings Future Conservation Needs 2 Clearwater - 17060306 Idaho 8 Digit Hydrologic Unit Profile December 2006 Relief Map 3 Clearwater - 17060306 Idaho 8 Digit Hydrologic Unit Profile December 2006 General Ownership 4 Clearwater - 17060306 Idaho 8 Digit Hydrologic Unit Profile December 2006 Physical Description /1 Ownership - (2003 Draft BLM Surface Map Set ) Land Cover/ Land Use Public Private Tribal % of /2 Totals (NLCD ) HUC Acres % Acres % Acres % Forest 243,323 16% 334,324 22% 26,553 2% 604,200 40% Grain Crops -- 486,616 32% 29,372 2% 515,988 34% Conservation Reserve /3 -- 49,030 3% 1,328 <1% 50,358 3% Program (CRP) Land Wetlands Reserve Program 95 95 <1% (WRP) Land Grass/Pasture/Hay Lands 9,782 <1% 131,815 9% 12,130 1% 153,727 10% Orchards/Vineyards/Berries -- -- -- -- Row Crops -- 657 <1% 83 <1% 740 <1% Shrub/Rangelands 12,382 1% 127,134 8% 12,370 1% 151,886 10% Water/Wetlands/ 5,680 <1% 22,607 2% 946 <1% 29,233 2% Developed/Barren Idaho HUC Totals* 271,167 18% 1,152,278 76% 82,782 6% 1,506,227 100% *Totals are approximate due to calculation methods used. % of % of Type of Land ACRES Irrigated Lands HUC /4 Cultivated Cropland 2,400 65% <1% Irrigated Lands Non-Cultivated Cropland** 1,300 35% <1% Pastureland 0 -- Total Irrigated Lands 3,700 100% <1% **Includes permanent hayland and horticultural cropland . 5 Clearwater - 17060306 Idaho 8 Digit Hydrologic Unit Profile December 2006 Land Use/Land Cover 6 Clearwater - 17060306 Idaho 8 Digit Hydrologic Unit Profile December 2006 Average Annual Precipitation 7 Clearwater - 17060306 Idaho 8 Digit Hydrologic Unit Profile December 2006 Common Resource Area Map CRA Map - areas with a majority are listed below - for descriptions of every class within the HUC, go to: http://ice.id.nrcs.usda.gov/website/cra/viewer.htm A Common Resource Area (CRA) is defined as a geographical area where resource concerns, problems, or treatment needs are similar. It is considered a subdivision of an existing Major Land Resource Area (MLRA) map delineation or polygon. Landscape conditions, soil, climate, human considerations, and other natural resource information are used to determine the geographic boundaries of a Common Resource Area. (General Manual Title 450 Subpart C 401.21 ) 8 Clearwater - 17060306 Idaho 8 Digit Hydrologic Unit Profile December 2006 Common Resource Area Descriptions The National Coordinated CRA Geographic Database provides: • A consistent CRA geographic database; • CRA geographic data compatible with other GIS data digitized from 1:250,000 scale maps, such as landuse/landcover, political boundaries, Digital General Soil Map of the U.S. (updated STATSGO), and ecoregion boundaries; • A consistent (correlated) geographic index for Conservation System Guides information and the eFOTG • A geographic linkage with the national MRLA framework 8.6 Columbia Plateau - Lower Snake and Clearwater Canyons This unit consists of deeply dissected canyons cut through the basalt layers of the Columbia Plateau. It has isolated plateau fragments of the Dissected Loess Uplands CRA. The depth of the canyons, up to 2,000 feet, create drier conditions and Mean annual precipitation decreases to about 10 inches at the bottom of these canyons. Outside of human population centers and transportation corridors, canyons provide wildlife habitat for bighorn sheep and game birds. Grass-covered: grazing, recreation, and wildlife habitat. 9.2 Palouse and Nez Perce Prairies - Palouse Hills This unit is the western foothills of the Northern Rocky Mountains. This unit is characterized by a non-forested, loess-covered area with greater than 15 inches of precipitation. The highly productive soil has a higher organic matter and clay content. Original plant cover has been almost entirely supplanted by wheat farms. Water erosion is the major management issue. Perennial streams originate from the mountains to the east. Smaller, loess-bottomed streams rise within the CRA and are intermittent. Many of these intermittent streams are plowed and tiled. Extensive farming including small grains, peas, lentils, hay and pastureland. 9.3 Palouse and Nez Perce Prairies - Dissected Loess Uplands This unit is located on the northeastern slopes of the Blue Mountains. It comprises non-forested, rolling loess hills, canyons, and flat plateau remnants isolated by the lower canyons of the Snake River (CRA 8.6). Grasslands without a sagebrush component dominate the lower elevations. Shrubs (rose and snowberry) appear with increasing moisture at higher elevations. Though grazing and farming have eliminated much of the original plant cover, the dissected terrain and thinner soil is not as suited to agriculture as the neighboring Palouse Hills and Deep Loess Foothills CRAs. Small grain, pea, and hay farming, grazing, and wildlife habitat. 9.11 Palouse and Nez Perce Prairies - Nez Perce Prairie This unit is a loess-covered plateau. It is higher, cooler, less hilly, and has shallower soils than the Palouse Hills CRA. Idaho fescue and bluebunch wheatgrass are native. Cropland is now extensive and grows wheat, barley, peas, and hay. The headwaters of many perennial streams are impacted by agricultural land use, negatively impacting the water quality of downstream canyon reaches. 9 Clearwater - 17060306 Idaho 8 Digit Hydrologic Unit Profile December 2006 Common Resource Area Descriptions - continued 43A.1 Northern Rocky Mountains - Grassy Potlatch Ridges The Grassy Potlatch Ridges ecoregion is underlain by volcanics and mantled by loess and volcanic ash. Idaho fescue, bluebunch wheatgrass, bluegrass, snowberry, and, on cooler, moister sites, scattered ponderosa pine occur and contrast with the forests of the Northern Idaho Hills and the forests and savannas of the Lower Clearwater Canyons. Today, small grain farming, hay operations, and livestock grazing are extensive. 43A.2 Northern Rocky Mountains - Clearwater Mountains and Breaks The Clearwater Mountains and Breaks ecoregion is exposed to substantial maritime influence, mantled by thick volcanic ash, and underlain by granitics. Its moist coniferous forests lack western hemlock and are transitional between those of the Idaho Panhandle and the drier forests of the southern Idaho Batholith. 43A.3 Northern Rocky Mountains - Lower Clearwater Canyons The deep, narrow Lower Clearwater Canyons are lower, drier, warmer, and have been more developed than the Lochsa-Selway-Clearwater Canyons. Savanna, Douglas-fir-ponderosa pine forest, and, in riparian areas, western red cedar-western white pine-grand fir forest occur. Forests are more widespread on canyon bottoms than on slopes. 43A.4 Northern Rocky Mountains - Weippe Prairie The Weippe Prairie ecoregion is a gently sloping basalt plateau that is mantled by loess and volcanic ash. Its mixed coniferous forest contains ponderosa pine, Douglas-fir, grand fir, western red cedar, and western larch. Hay